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                    Introduction
            
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                    第零章：实验环境说明
            
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                    第一章：独立式可执行程序
            
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                    使用包管理器 cargo 创建 rust binary 项目
            
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                    [移除 runtime 依赖]
            
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                    使用链接脚本指定内存布局
            
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                    [重写程序入口点 -start]
            
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                    [使用 Qemu 运行内核]
            
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                    封装 SBI 接口
            
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                    [实现格式化输出]
            
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                    总结与展望
            
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                    第三章：中断
            
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                    rv64 中断介绍
            
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                    [手动触发断点中断]
            
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                    程序运行上下文环境
            
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                    [实现上下文环境保存与恢复]
            
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                    [时钟中断]
            
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                    总结与展望
            
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                    第四章：内存管理
            
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                    [物理内存探测与管理]
            
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                    [动态内存分配]
            
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                    总结与展望
            
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                    第五章：内存虚拟化
            
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                    页表：从虚拟内存到物理内存
            
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                    [内核初始映射]
            
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                    内核重映射
            
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                    内核重映射实现之一：页表
            
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                    内核重映射实现之二：MemorySet
            
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                    [内核重映射实现之三：完结]
            
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                    总结与展望
            
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                    第六章：内核线程
            
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                    线程状态与保存
            
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                    线程切换
            
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                    内核线程初始化
            
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                    [内核线程创建与切换测试]
            
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                    总结与展望
            
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                    第七章：线程调度
            
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                    线程池与线程管理
            
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                    内核调度线程 idle
            
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                    线程调度之 Round Robin 算法
            
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                    [线程调度测试]
            
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                    总结与展望
            
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                    第八章：进程
            
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                    [编写用户程序]
            
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                    合并内核与应用程序
            
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                    在内核中实现系统调用
            
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                    创建虚拟内存空间
            
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                    [创建进程]
            
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                    总结与展望
            
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                    第九章：文件系统
            
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                    [实现终端]
            
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                    [文件读写]
            
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                    总结与展望
            
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                    第十章：同步互斥
            
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                    1. 中断异常
            
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                    2. 物理内存管理
            
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                    3. 虚拟内存管理
            
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                    4. 线程管理
            
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                    5. 用户进程（+ 虚拟内存管理 + 线程管理）
            
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                    6. CPU 调度
            
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                    7. 同步互斥
            
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                    8. 文件系统
            
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                    附录
            
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                    内联汇编
            
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                    安装 rust
            
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</ul>
<p>&#x6211;&#x4EEC;&#x5728;&#x7B2C;&#x4E00;&#x7AE0;&#x4E2D;&#xFF0C;&#x66FE;&#x81EA;&#x5DF1;&#x91CD;&#x5199;&#x4E86;&#x4E00;&#x4E2A; C runtime &#x7684;&#x5165;&#x53E3;&#x70B9; <code>_start</code> &#xFF0C;&#x5728;&#x90A3;&#x91CC;&#x6211;&#x4EEC;&#x4EC5;&#x4EC5;&#x53EA;&#x662F;&#x8BA9;&#x5B83;&#x6B7B;&#x5FAA;&#x73AF;&#x3002;&#x4F46;&#x662F;&#x73B0;&#x5728;&#xFF0C;&#x7C7B;&#x4F3C; C runtime &#xFF0C;&#x6211;&#x4EEC;&#x5E0C;&#x671B;&#x8FD9;&#x4E2A;&#x51FD;&#x6570;&#x53EF;&#x4EE5;&#x4E3A;&#x6211;&#x4EEC;&#x8BBE;&#x7F6E;&#x5185;&#x6838;&#x7684;&#x8FD0;&#x884C;&#x73AF;&#x5883;(&#x4E0D;&#x59A8;&#x79F0;&#x4E3A; kernel runtime ) &#x3002;&#x968F;&#x540E;&#xFF0C;&#x6211;&#x4EEC;&#x624D;&#x771F;&#x6B63;&#x5F00;&#x59CB;&#x6267;&#x884C;&#x5185;&#x6838;&#x7684;&#x4EE3;&#x7801;&#x3002;</p>
<p>&#x4F46;&#x662F;&#x5177;&#x4F53;&#x800C;&#x8A00;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x8BBE;&#x7F6E;&#x600E;&#x6837;&#x7684;&#x8FD0;&#x884C;&#x73AF;&#x5883;&#x5462;&#xFF1F;</p>
<blockquote>
<p><strong>[info] &#x7B2C;&#x4E00;&#x6761;&#x6307;&#x4EE4;</strong></p>
<p>&#x5728; CPU &#x52A0;&#x7535;&#x6216; reset &#x540E;&#xFF0C;&#x5B83;&#x9996;&#x5148;&#x4F1A;&#x8FDB;&#x884C; <strong>&#x81EA;&#x68C0; (POST, Power-On Self-Test)</strong> &#xFF0C;&#x901A;&#x8FC7;&#x81EA;&#x68C0;&#x540E;&#x4F1A;&#x8DF3;&#x8F6C;&#x5230; <strong>&#x542F;&#x52A8;&#x4EE3;&#x7801;(bootloader)</strong> &#x7684;&#x5165;&#x53E3;&#x3002;&#x5728; bootloader &#x4E2D;&#xFF0C;&#x6211;&#x4EEC;&#x8FDB;&#x884C;&#x5916;&#x8BBE;&#x63A2;&#x6D4B;&#xFF0C;&#x5E76;&#x5BF9;&#x5185;&#x6838;&#x7684;&#x8FD0;&#x884C;&#x73AF;&#x5883;&#x8FDB;&#x884C;&#x521D;&#x6B65;&#x8BBE;&#x7F6E;&#x3002;&#x968F;&#x540E;&#xFF0C; bootloader &#x4F1A;&#x5C06;&#x5185;&#x6838;&#x4EE3;&#x7801;&#x4ECE;&#x786C;&#x76D8; load &#x5230;&#x5185;&#x5B58;&#x4E2D;&#xFF0C;&#x5E76;&#x8DF3;&#x8F6C;&#x5230;&#x5185;&#x6838;&#x5165;&#x53E3;&#xFF0C;&#x6B63;&#x5F0F;&#x8FDB;&#x5165;&#x5185;&#x6838;&#x3002;</p>
<p>&#x6240;&#x4EE5; CPU &#x6240;&#x6267;&#x884C;&#x7684;&#x7B2C;&#x4E00;&#x6761;&#x6307;&#x4EE4;&#x662F;&#x6307; bootloader &#x7684;&#x7B2C;&#x4E00;&#x6761;&#x6307;&#x4EE4;&#x3002;</p>
</blockquote>
<p>&#x5E78;&#x8FD0;&#x7684;&#x662F;&#xFF0C; &#x6211;&#x4EEC;&#x5DF2;&#x7ECF;&#x6709;&#x73B0;&#x6210;&#x7684; bootloader &#x5B9E;&#x73B0; -- <a href="https://github.com/riscv/opensbi" target="_blank">OpenSBI</a> &#x56FA;&#x4EF6;(firmware)&#x3002;</p>
<blockquote>
<p><strong>[info] firmware &#x56FA;&#x4EF6;</strong></p>
<p>&#x5728;&#x8BA1;&#x7B97;&#x4E2D;&#xFF0C;&#x56FA;&#x4EF6;&#x662F;&#x4E00;&#x79CD;&#x7279;&#x5B9A;&#x7684;&#x8BA1;&#x7B97;&#x673A;&#x8F6F;&#x4EF6;&#xFF0C;&#x5B83;&#x4E3A;&#x8BBE;&#x5907;&#x7684;&#x7279;&#x5B9A;&#x786C;&#x4EF6;&#x63D0;&#x4F9B;&#x4F4E;&#x7EA7;&#x63A7;&#x5236;&#x8FDB;&#x4E00;&#x6B65;&#x52A0;&#x8F7D;&#x5176;&#x4ED6;&#x8F6F;&#x4EF6;&#x7684;&#x529F;&#x80FD;&#x3002;&#x56FA;&#x4EF6;&#x53EF;&#x4EE5;&#x4E3A;&#x8BBE;&#x5907;&#x66F4;&#x590D;&#x6742;&#x7684;&#x8F6F;&#x4EF6;&#xFF08;&#x5982;&#x64CD;&#x4F5C;&#x7CFB;&#x7EDF;&#xFF09;&#x63D0;&#x4F9B;&#x6807;&#x51C6;&#x5316;&#x7684;&#x64CD;&#x4F5C;&#x73AF;&#x5883;&#xFF0C;&#x6216;&#x8005;&#xFF0C;&#x5BF9;&#x4E8E;&#x4E0D;&#x592A;&#x590D;&#x6742;&#x7684;&#x8BBE;&#x5907;&#xFF0C;&#x5145;&#x5F53;&#x8BBE;&#x5907;&#x7684;&#x5B8C;&#x6574;&#x64CD;&#x4F5C;&#x7CFB;&#x7EDF;&#xFF0C;&#x6267;&#x884C;&#x6240;&#x6709;&#x63A7;&#x5236;&#x3001;&#x76D1;&#x89C6;&#x548C;&#x6570;&#x636E;&#x64CD;&#x4F5C;&#x529F;&#x80FD;&#x3002; &#x5728;&#x57FA;&#x4E8E; x86 &#x7684;&#x8BA1;&#x7B97;&#x673A;&#x7CFB;&#x7EDF;&#x4E2D;, BIOS &#x6216; UEFI &#x662F;&#x4E00;&#x79CD;&#x56FA;&#x4EF6;&#xFF1B;&#x5728;&#x57FA;&#x4E8E; riscv &#x7684;&#x8BA1;&#x7B97;&#x673A;&#x7CFB;&#x7EDF;&#x4E2D;&#xFF0C;OpenSBI &#x662F;&#x4E00;&#x79CD;&#x56FA;&#x4EF6;&#x3002;</p>
</blockquote>
<p>OpenSBI &#x56FA;&#x4EF6;&#x8FD0;&#x884C;&#x5728;&#x7279;&#x6743;&#x7EA7;&#x522B;&#x5F88;&#x9AD8;&#x7684;&#x8BA1;&#x7B97;&#x673A;&#x786C;&#x4EF6;&#x73AF;&#x5883;&#x4E2D;&#xFF0C;&#x5373; riscv64 cpu &#x7684; M Mode (CPU &#x52A0;&#x7535;&#x540E;&#x4E5F;&#x5C31;&#x8FD0;&#x884C;&#x5728; M Mode) &#xFF0C;&#x6211;&#x4EEC;&#x5C06;&#x8981;&#x5B9E;&#x73B0;&#x7684; OS &#x5185;&#x6838;&#x8FD0;&#x884C;&#x5728; S Mode &#xFF0C; &#x800C;&#x6211;&#x4EEC;&#x8981;&#x652F;&#x6301;&#x7684;&#x7528;&#x6237;&#x7A0B;&#x5E8F;&#x8FD0;&#x884C;&#x5728; U Mode &#x3002;&#x5728;&#x5F00;&#x53D1;&#x8FC7;&#x7A0B;&#x4E2D;&#x6211;&#x4EEC;&#x91CD;&#x70B9;&#x5173;&#x6CE8; S Mode &#x3002;</p>
<blockquote>
<p><strong>[info] riscv64 &#x7684;&#x7279;&#x6743;&#x7EA7;</strong></p>
<p>&#x5982;&#x56FE;&#x6240;&#x793A;&#xFF0C;&#x5171;&#x6709;&#x5982;&#x4E0B;&#x51E0;&#x4E2A;&#x7279;&#x6743;&#x7EA7;&#xFF1A;</p>
<p><img src="figures/privilege_levels.png" alt=""></p>
<p>&#x4ECE; U &#x5230; S &#x518D;&#x5230; M&#xFF0C;&#x6743;&#x9650;&#x4E0D;&#x65AD;&#x63D0;&#x9AD8;&#xFF0C;&#x8FD9;&#x610F;&#x5473;&#x7740;&#x4F60;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x66F4;&#x591A;&#x7684;&#x7279;&#x6743;&#x6307;&#x4EE4;&#xFF0C;&#x8BBF;&#x9700;&#x6C42;&#x6743;&#x9650;&#x66F4;&#x9AD8;&#x7684;&#x5BC4;&#x5B58;&#x5668;&#x7B49;&#x7B49;&#x3002;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x4E00;&#x4E9B;&#x6307;&#x4EE4;&#x6765;&#x4FEE;&#x6539; CPU &#x7684;<strong>&#x5F53;&#x524D;&#x7279;&#x6743;&#x7EA7;</strong>&#x3002;&#x800C;&#x5F53;&#x5F53;&#x524D;&#x7279;&#x6743;&#x7EA7;&#x4E0D;&#x8DB3;&#x4EE5;&#x6267;&#x884C;&#x7279;&#x6743;&#x6307;&#x4EE4;&#x6216;&#x8BBF;&#x95EE;&#x4E00;&#x4E9B;&#x5BC4;&#x5B58;&#x5668;&#x65F6;&#xFF0C;CPU &#x4F1A;&#x901A;&#x8FC7;&#x67D0;&#x79CD;&#x65B9;&#x5F0F;&#x544A;&#x8BC9;&#x6211;&#x4EEC;&#x3002;</p>
</blockquote>
<p>OpenSBI &#x6240;&#x505A;&#x7684;&#x4E00;&#x4EF6;&#x4E8B;&#x60C5;&#x5C31;&#x662F;&#x628A; CPU &#x4ECE; M Mode &#x5207;&#x6362;&#x5230; S Mode &#xFF0C;&#x63A5;&#x7740;&#x8DF3;&#x8F6C;&#x5230;&#x4E00;&#x4E2A;&#x56FA;&#x5B9A;&#x5730;&#x5740; 0x80200000&#xFF0C;&#x5F00;&#x59CB;&#x6267;&#x884C;&#x5185;&#x6838;&#x4EE3;&#x7801;&#x3002;</p>
<blockquote>
<p><strong>[info] riscv64 &#x7684; M Mode</strong></p>
<p>M-mode(&#x673A;&#x5668;&#x6A21;&#x5F0F;&#xFF0C;&#x7F29;&#x5199;&#x4E3A; M &#x6A21;&#x5F0F;)&#x662F; RISC-V &#x4E2D; hart(hardware thread,&#x786C;&#x4EF6;&#x7EBF;&#x7A0B;)&#x53EF;&#x4EE5;&#x6267;&#x884C;&#x7684;&#x6700;&#x9AD8;&#x6743;&#x9650;&#x6A21;&#x5F0F;&#x3002;&#x5728; M &#x6A21;&#x5F0F;&#x4E0B;&#x8FD0;&#x884C;&#x7684; hart &#x5BF9;&#x5185;&#x5B58;,I/O &#x548C;&#x4E00;&#x4E9B;&#x5BF9;&#x4E8E;&#x542F;&#x52A8;&#x548C;&#x914D;&#x7F6E;&#x7CFB;&#x7EDF;&#x6765;&#x8BF4;&#x5FC5;&#x8981;&#x7684;&#x5E95;&#x5C42;&#x529F;&#x80FD;&#x6709;&#x7740;&#x5B8C;&#x5168;&#x7684;&#x4F7F;&#x7528;&#x6743;&#x3002;</p>
<p><strong>riscv64 &#x7684; S Mode</strong></p>
<p>S-mode(&#x76D1;&#x7BA1;&#x8005;&#x6A21;&#x5F0F;&#xFF0C;&#x7F29;&#x5199;&#x4E3A; S &#x6A21;&#x5F0F;)&#x662F;&#x652F;&#x6301;&#x73B0;&#x4EE3;&#x7C7B; Unix &#x64CD;&#x4F5C;&#x7CFB;&#x7EDF;&#x7684;&#x6743;&#x9650;&#x6A21;&#x5F0F;&#xFF0C;&#x652F;&#x6301;&#x73B0;&#x4EE3;&#x7C7B; Unix &#x64CD;&#x4F5C;&#x7CFB;&#x7EDF;&#x6240;&#x9700;&#x8981;&#x7684;&#x57FA;&#x4E8E;&#x9875;&#x9762;&#x7684;&#x865A;&#x62DF;&#x5185;&#x5B58;&#x673A;&#x5236;&#x662F;&#x5176;&#x6838;&#x5FC3;&#x3002;</p>
</blockquote>
<p>&#x63A5;&#x7740;&#x6211;&#x4EEC;&#x8981;&#x5728; <code>_start</code> &#x4E2D;&#x8BBE;&#x7F6E;&#x5185;&#x6838;&#x7684;&#x8FD0;&#x884C;&#x73AF;&#x5883;&#x4E86;&#xFF0C;&#x6211;&#x4EEC;&#x76F4;&#x63A5;&#x6765;&#x770B;&#x4EE3;&#x7801;&#xFF1A;</p>
<pre class="language-"><code class="lang-riscv"><span class="token comment"># src/boot/entry64.asm
</span>
    <span class="token section-directives tag">.section</span> <span class="token section-directives tag">.text</span>.<span class="token last-literals operator">entry</span>
    <span class="token symbol-directives tag">.globl</span> <span class="token last-literals operator">_start</span>
<span class="token labels operator">_start:</span>
    <span class="token pseudo-instructions important">la</span> <span class="token general-registers class-name">sp</span>, <span class="token last-literals operator">bootstacktop</span>
    <span class="token pseudo-instructions important">call</span> <span class="token last-literals operator">rust_main</span>

    <span class="token section-directives tag">.section</span> <span class="token section-directives tag">.bss</span>.<span class="token last-literals operator">stack</span>
    <span class="token alignment-directives tag">.align</span> <span class="token number">12</span>
    .<span class="token last-literals operator">global</span> <span class="token last-literals operator">bootstack</span>
<span class="token labels operator">bootstack:</span>
    .<span class="token last-literals operator">space</span> <span class="token number">4096</span> * <span class="token number">4</span>
    .<span class="token last-literals operator">global</span> <span class="token last-literals operator">bootstacktop</span>
<span class="token labels operator">bootstacktop:</span>
</code></pre>
<p>&#x53EF;&#x4EE5;&#x770B;&#x5230;&#x4E4B;&#x524D;&#x672A;&#x88AB;&#x5B9A;&#x4E49;&#x7684; <em>.bss.stack</em> &#x6BB5;&#x51FA;&#x73B0;&#x4E86;&#xFF0C;&#x6211;&#x4EEC;&#x53EA;&#x662F;&#x5728;&#x8FD9;&#x91CC;&#x5206;&#x914D;&#x4E86;&#x4E00;&#x5757; <span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>4</mn><mn>0</mn><mn>9</mn><mn>6</mn><mo>&#xD7;</mo><mrow><mn>4</mn></mrow><mtext><mi mathvariant="normal">B</mi><mi mathvariant="normal">y</mi><mi mathvariant="normal">t</mi><mi mathvariant="normal">e</mi><mi mathvariant="normal">s</mi></mtext><mo>=</mo><mtext><mn>1</mn><mn>6</mn><mi mathvariant="normal">K</mi><mi mathvariant="normal">i</mi><mi mathvariant="normal">B</mi></mtext></mrow><annotation encoding="application/x-tex">4096\times{4}\text{Bytes}=\text{16KiB}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="strut" style="height:0.68333em;"></span><span class="strut bottom" style="height:0.8777699999999999em;vertical-align:-0.19444em;"></span><span class="base textstyle uncramped"><span class="mord mathrm">4</span><span class="mord mathrm">0</span><span class="mord mathrm">9</span><span class="mord mathrm">6</span><span class="mbin">&#xD7;</span><span class="mord textstyle uncramped"><span class="mord mathrm">4</span></span><span class="mord text textstyle uncramped"><span class="mord mathrm">Bytes</span></span><span class="mrel">=</span><span class="mord text textstyle uncramped"><span class="mord mathrm">16KiB</span></span></span></span></span> &#x7684;&#x5185;&#x5B58;&#x4F5C;&#x4E3A;&#x5185;&#x6838;&#x7684;&#x6808;&#x3002;&#x4E4B;&#x524D;&#x7684; <em>.text.entry</em> &#x4E5F;&#x51FA;&#x73B0;&#x4E86;&#xFF1A;&#x6211;&#x4EEC;&#x5C06; <code>_start</code> &#x51FD;&#x6570;&#x653E;&#x5728;&#x4E86; <em>.text</em> &#x6BB5;&#x7684;&#x5F00;&#x5934;&#x3002;</p>
<p>&#x6211;&#x4EEC;&#x770B;&#x770B; <code>_start</code> &#x91CC;&#x9762;&#x505A;&#x4E86;&#x4EC0;&#x4E48;&#xFF1A;</p>
<ol>
<li>&#x4FEE;&#x6539;&#x6808;&#x6307;&#x9488;&#x5BC4;&#x5B58;&#x5668; <code>sp</code> &#x4E3A; <em>.bss.stack</em> &#x6BB5;&#x7684;&#x7ED3;&#x675F;&#x5730;&#x5740;&#xFF0C;&#x7531;&#x4E8E;&#x6808;&#x662F;&#x4ECE;&#x9AD8;&#x5730;&#x5740;&#x5F80;&#x4F4E;&#x5730;&#x5740;&#x589E;&#x957F;&#xFF0C;&#x6240;&#x4EE5;&#x9AD8;&#x5730;&#x5740;&#x662F;&#x6808;&#x9876;&#xFF1B;</li>
<li>&#x4F7F;&#x7528; <code>call</code> &#x6307;&#x4EE4;&#x8DF3;&#x8F6C;&#x5230; <code>rust_main</code> &#x3002;&#x8FD9;&#x610F;&#x5473;&#x7740;&#x6211;&#x4EEC;&#x7684;&#x5185;&#x6838;&#x8FD0;&#x884C;&#x73AF;&#x5883;&#x8BBE;&#x7F6E;&#x5B8C;&#x6210;&#x4E86;&#xFF0C;&#x6B63;&#x5F0F;&#x8FDB;&#x5165;&#x5185;&#x6838;&#x3002;</li>
</ol>
<p>&#x6211;&#x4EEC;&#x5C06; <code>src/main.rs</code> &#x91CC;&#x9762;&#x7684; <code>_start</code> &#x51FD;&#x6570;&#x5220;&#x9664;&#xFF0C;&#x5E76;&#x6362;&#x6210; <code>rust_main</code> &#xFF1A;</p>
<pre class="language-"><code class="lang-rust"><span class="token comment">// src/main.rs</span>

<span class="token attribute attr-name">#![feature(global_asm)]</span>

<span class="token macro property">global_asm!</span><span class="token punctuation">(</span><span class="token macro property">include_str!</span><span class="token punctuation">(</span><span class="token string">&quot;boot/entry64.asm&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token attribute attr-name">#[no_mangle]</span>
<span class="token keyword">pub</span> <span class="token keyword">extern</span> <span class="token string">&quot;C&quot;</span> <span class="token keyword">fn</span> <span class="token function-definition function">rust_main</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">-&gt;</span> <span class="token operator">!</span> <span class="token punctuation">{</span>
    <span class="token keyword">loop</span> <span class="token punctuation">{</span><span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre>
<p>&#x5230;&#x73B0;&#x5728;&#x4E3A;&#x6B62;&#x6211;&#x4EEC;&#x7EC8;&#x4E8E;&#x5C06;&#x4E00;&#x5207;&#x90FD;&#x51C6;&#x5907;&#x597D;&#x4E86;&#xFF0C;&#x63A5;&#x4E0B;&#x6765;&#x5C31;&#x8981;&#x914D;&#x5408; OpenSBI &#x8FD0;&#x884C;&#x6211;&#x4EEC;&#x7684;&#x5185;&#x6838;&#xFF01;</p>
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